Before the Iraq war, Saddam Hussein misjudged the U.S. military strategy and thought the United States would launch only several days of airstrikes and not a full-scale ground invasion, according to a television interview with the FBI agent who interrogated the former Iraqi leader for seven months.

FBI agent George Piro said that Hussein told him he "initially miscalculated . . . President Bush's intentions," according to a news release from CBS News, which will air the interview with Piro on "60 Minutes" tomorrow.

Hussein "thought the United States would retaliate with the same type of attack as we did in 1998 . . . a four-day aerial attack," Piro said in the interview, according to CBS. "He survived that one and he was willing to accept that type of attack." Hussein was later put on trial and was executed by hanging in December 2006.

Piro, a Lebanese American and one of only about 50 Arabic-speaking agents in the FBI, became Hussein's sole debriefer beginning in January 2004, shortly after the fugitive Iraqi leader was captured by the U.S. military in a "spider hole" near his ancestral home of Tikrit.

Realizing how defiant Hussein was, Piro adopted the only interrogation strategy he believed would elicit the truth: He presented himself as a high-ranking envoy who answered directly to President Bush, and tried to win Hussein's confidence during a series of long conversations, according to CBS.

Piro also said that he sought to gain influence with Hussein by serving as the former leader's only provider of basic necessities such as paper for writing poetry and toiletries, according to CBS.

Even when Hussein realized that U.S. military action was imminent, he sought to continue to project a strong image because of his worries about a potential Iranian invasion, Piro said. "For him, it was critical that he was seen as still the strong, defiant Saddam. He thought that . . . would prevent the Iranians from reinvading Iraq," Piro is quoted by CBS as saying.

Hussein's strategy upon facing the U.S. invasion was to tell his generals to try to hold back the U.S. forces for two weeks, "and at that point, it would go into what he called the secret war," Piro said, referring to the Iraqi insurgency.

Hussein bragged about escaping airstrikes and evading capture for several months after the fall of Baghdad, Piro said in the interview. "What he wanted to really illustrate is . . . how he was able to outsmart us," Piro said. "He told me he changed . . . the way he traveled. He got rid of his normal vehicles. He got rid of the protective detail that he traveled with, really just to change his signature."

In the course of several face-to-face discussions, Piro said Hussein also told him that the incident that finally led him to decide to invade Kuwait in 1990 was a personal insult by the emir there.

"What really triggered it for him, according to Saddam, was he had sent his foreign minister to Kuwait to meet with the emir al-Sabah . . . to try to resolve some of these issues. And the emir told the foreign minister of Iraq that he would not stop doing what he was doing until he turned every Iraqi woman into a $10 prostitute. And that really sealed it for him, to invade Kuwait," Piro said in the interview, according to CBS.